This 3-year project will examine childhood predictors of sexual behaviors that place adolescents at risk for HIV infection. Secondary data analysis of the National Longitudinal Survey of Youth (NLSY) mother-child data set will be conducted: (1) To identify individual, family, and peer factors operating in childhood and adolescence that predispose adolescents to sexual risk-taking; (2) To identify protective factors (particularly parenting practices) that reduce the likelihood that high risk adolescents will engage in sexual risk-taking; (3) To examine the stability and early predictors of self-regulation; (4) To test a comprehensive predictive model of adolescent sexual risk-taking across gender and ethnic/racial groups. The target sample consists of children of original NLSY participants who were 4-5 years old in 1986 and who have data at four time points: 1986, 1990, 1994, 1998 (estimated N = 600). In Phase 1, data from the 1998 Child Supplement (due out in May 2000) will be configured and integrated with existing longitudinal data from 1986, 1990, and 1994, and preliminary analyses will be conducted. In Phase 2, predictors of adolescent sexual risk-taking will be examined, with particular attention to self-regulation, risk proneness, and peer influences. Factors that mitigate risk (e.g., effective parenting, non-deviant peers) will also be examined. Predictive models of adolescent sexual risk-taking will be tested across gender and ethnic/racial groups (Black, Hispanic, and White non-Hispanic). Phase 3 will focus on identifying early and concurrent predictors of middle childhood self-regulation, examining the stability of self-regulation in childhood and adolescence, and identifying trajectories of self-regulation across childhood. Finally, in Phase 4, replication analyses on a cohort of NLSY children born to older mothers will be conducted to determine the robustness and generalizability of the findings. This project will provide unique information about developmental antecedents of adolescent sexual risk-taking and permit identification of fruitful avenues for early intervention.